Writing to Excel workbook using javascript and xlsx library gives error

(function(){ var urlJSZip ="https://cdnjs.cloudflare.com/ajax/libs/jszip/3.1.3/jszip.min.js"; var urlXLSX ="https://cdnjs.cloudflare.com/ajax/libs/xlsx/0.9.2/xlsx.core.min.js"; var urlFileSaver ="https://cdnjs.cloudflare.com/ajax/libs/FileSaver.js/1.3.3/FileSaver.js";  $.when($.getScript(urlJSZip), $.getScript(urlXLSX), $.getScript(urlFileSaver)).then(function() {

   /* original data */  var data = [[1,2,3],,["foo","bar",new Date("2014-02-19T14:30Z"), "0.3"], ["baz", null, "qux"]]  var ws_name = "SheetJS";    var wb = new Workbook(), ws = sheet_from_array_of_arrays(data);     /* add worksheet to workbook */  wb.SheetNames.push(ws_name);  wb.Sheets[ws_name] = ws;  var wbout = XLSX.write(wb, {bookType:'xlsx', bookSST:true, type: 'binary'});      saveAs(new Blob([s2ab(wbout)],{type:"application/octet-stream"}), "test.xlsx") });  function datenum(v, date1904) {  if(date1904) v+=1462;  var epoch = Date.parse(v);  return (epoch - new Date(Date.UTC(1899, 11, 30))) / (24 * 60 * 60 * 1000); }   function sheet_from_array_of_arrays(data, opts) {  var ws = {};  var range = {s: {c:10000000, r:10000000}, e: {c:0, r:0 }};  for(var R = 0; R != data.length; ++R) {   for(var C = 0; C != data.length; ++C) {    if(range.s.r > R) range.s.r = R;    if(range.s.c > C) range.s.c = C;    if(range.e.r < R) range.e.r = R;    if(range.e.c < C) range.e.c = C;    var cell = {v: data };    if(cell.v == null) continue;    var cell_ref = XLSX.utils.encode_cell({c:C,r:R});        if(typeof cell.v === 'number') cell.t = 'n';    else if(typeof cell.v === 'boolean') cell.t = 'b';    else if(cell.v instanceof Date) {     cell.t = 'n'; cell.z = XLSX.SSF._table[14];     cell.v = datenum(cell.v);    }    else cell.t = 's';        ws[cell_ref] = cell;   }  }  if(range.s.c < 10000000) ws['!ref'] = XLSX.utils.encode_range(range);  return ws; }    function Workbook() {  if(!(this instanceof Workbook)) return new Workbook();  this.SheetNames = [];  this.Sheets = {}; }    function s2ab(s) {  var buf = new ArrayBuffer(s.length);  var view = new Uint8Array(buf);  for (var i=0; i!=s.length; ++i) view = s.charCodeAt(i) & 0xFF;  return buf; } })();